1.Three-dimensional finite element analysis of the effect of orbital implant lengths on stress distributions in peri-implant surfaces.
Xing ZHANG ; Songling CHEN ; Yun ZHANG ; Liuying QI
West China Journal of Stomatology 2014;32(5):484-487
OBJECTIVEThis study aims to observe the effect of orbital implant lengths on stress distribution in peri-implant surfaces.
METHODSThe three-dimensional finite element analysis models of craniofacial and orbital implants with a diameter of 3.75 mm and lengths of 3, 4, 6, and 10 mm were established. A force of 20 N was applied to the models. The stress and displacement distribution under every condition were recorded and analyzed.
RESULTSThe loading direction along the implant axis and the stress concentration on the implant root were observed. The loading direction was at a 45 degree angle relative to the implant axis, and the stress concentration was located at the implant neck and the first screw thread. The maximum stress of the 3 mm implant was significantly higher than that under the other two loading directions. The maximum displacement of the four lengths exhibited no significant change. Given the same implant length, stress, and displacement, the peak of the implant axial direction was lower than that of the 45 degree direction. The loading type was an important factor influencing the stress and displacement of peri-implant bones.
CONCLUSIONThe implants of more than 4 mm length can be considered for clinical use. The implant of 3 mm length should be implanted in a region with thicker cortical bone.
Biomechanical Phenomena ; Dental Implants ; Dental Prosthesis Design ; Dental Stress Analysis ; Finite Element Analysis ; Orbital Implants ; Stress, Mechanical
2.Simplified MELD Score Accurately Classifies HBV-related Cirrhotic Patients with Acute Decompensation into Different Short-term Prognostic Groups
Liuying CHEN ; Shan YIN ; Shijin WANG ; Nannan ZHANG ; Hai LI
Chinese Journal of Gastroenterology 2016;21(5):263-267
Background:For patients with liver cirrhosis and acute decompensation(AD),it is of great clinical importance to predict short-term mortality at admission. It has been reported that CLIF-C OF,MELD and MELD-Na score can accurately predict the short-term mortality,but all these scoring systems are complicated and have limits in their application. Aims:To define a simple and objective scoring system -- simplified MELD score for short-term mortality prediction in HBV-related cirrhotic patients with AD. Methods:A total of 890 consecutive HBV-related cirrhotic patients with AD hospitalized during Jan. 2005 to Dec. 2010 at Shanghai Ren Ji Hospital were enrolled retrospectively. Clinical data and patients’outcome were collected,and simplified MELD score was calculated by using total bilirubin,international normalized ratio and creatinine values at admission. Patients were classified into different prognostic groups according to their 28-day mortalities and simplified MELD score. Kaplan-Meier survival curve was used to analyze the 1-year accumulate survival rate,and ROC curve was used to evaluate the performance of different scoring systems in predicting 28-day mortality. Results:Simplified MELD score at admission could classify HBV-related cirrhotic patients with AD into low,moderate and high 28-day mortality groups and different long-term prognostic groups;the score of low,moderate and high 28-day mortality group was 0-2,3 and 4-6,respectively,and the corresponding mortality was 5. 5% ,19. 8% and 48. 6% ,respectively. Simplified MELD score had the same good performance as compared with the CLIF-C OF,MELD and MELD-Na scores in predicting 28-day mortality,the area under ROC curve was 0. 828,0. 831,0. 828 and 0. 830,respectively. Conclusions:Simplified MELD score can accurately classify HBV-related cirrhotic patients with AD into low,moderate and high 28-day mortality groups at admission. It is convenient for using in clinical practice.
3.Clinical Observation of Yinhe Gargle for Disinfection of Infected Root Canals
Liuying QI ; Zhongli CHEN ; Xing ZHANG ; Ying LIU ; Yinghong ZHANG
Journal of Guangzhou University of Traditional Chinese Medicine 2014;(5):743-745
Objective To evaluate the clinical efficacy of Yinhe gargle on infected root canals. Methods Forty-seven cases of root canal infection ( involving 48 affected teeth) were randomly divided into two groups. The experimental group (22 cases involving 22 affected teeth) was given intracanal medicament with Yinhe gargle, and the control group ( 25 cases involving 26 affected teeth) was given root canal disinfection with camphor phenol. After intracanal medicament for one week, therapeutic effect and safety were evaluated in the two groups. Results ( 1) During root canal disinfection, none of the subjects had adverse reaction such as hypersensitiveness or cauterization of soft tissue. Canal obturation was available after the first intracanal medicament for the infected root canals. (2) After intracanal medicament for one week, the effective rate in the experimental group was 95.45%, and was 100.00%in the control group, the difference being in significant (P>0.05). Conclusion Yinhe gargle has similar disinfection effect to camphor phenol on infected root canals, and it can be used as disinfection medicament for root canals.
4.Value of three-vessel and trachea view plus aortic arch coronal section in ultrasonic diagnosis and classification of fetal right aortic arch
Lin CHEN ; Liuying ZHOU ; Fangli LIU ; Zexuan YANG ; Liwen YANG ; Hua CHEN ; Hui HE ; Fengqin LIU
Chinese Journal of Ultrasonography 2017;26(6):505-509
Objective To explore the value of three-vessel and trachea(3VT) view plus aortic arch coronal section in ultrasonic diagnosis and classification of fetal right aortic arch(RAA).Methods Echocardiography data and follow-up results of 44 fetuses with RAA were retrospectively analyzed.Sonographic features on 3VT view and aortic arch coronal section were summarized.Results Among 44 fetuses with RAA,27 cases(61.36%) were RAA with aberrant left subclavian artery(ALSA) and the left ductus arteriosus(LDA) connecting the ALSA and U-shaped vascular ring was formed;17 cases(38.64%) were mirror right aortic arch(MRAA).Among 17 cases with MRAA,3 cases were with LDA connecting the descending aorta(DAO) and U-shaped vascular ring was formed;1 case was with LDA connecting the left innominate artery(LINA),8 cases were with absent ductus arteriosus(ADA),5 case were with right ductus arteriosus(RDA),no vascular ring was formed.Parts of MRAA were combined with other complex intracardiac abnormalities.RAA-ALSA-LDA were rarely combined with intracardiac abnormalities.Conclusions 3VT view is simple and intuitive for diagnosing RAA.Aortic arch coronal section has great clinical value in determining the concrete type of RAA.
5.The effect of orbital implant load angle on the stress distributions of peri-implant surface
Xing ZHANG ; Songxin XIA ; Songling CHEN ; Jianling CHEN ; Yun ZHANG ; Liuying QI
Journal of Practical Stomatology 2015;(2):237-240
Objective:To observe the effect of orbital implant load angle on the stress distribution of peri-implant surface.Methods:The 3D finite element analysis model of orbital implant with diameter of 3.75 mm and length of 6 mm was established.A force of 20 N was applied on the model at various angles.The stress distribution and displacement of the implant were recorded and analyzed.Results:Under 0°,1 0°,20°,30°,45°and 90°the maximum stress(MPa)on the peri-implant surface was 3.1 73,6.535,1 0.506,1 4.1 68, 1 8.949 and 24.755,the maximum displacement(μm)of the implant was 1 .761 ,3.654,7.665,1 1 .567,1 6.774 and 25.072,respec-tively.Conclusion:The loading angle is an important factor influencing stress and displacement of peri-implant bone.
6.Vascularised medial femoral condylar osteochondral chimeric tissue flap for repairing a complex tissue defect in metatarsal head: A case report
Kai ZHANG ; Cai QI ; Jun XIE ; Baocheng CANG ; Jia CHEN ; Ruifu YANG ; Liuying SHAO ; Mingwu ZHOU
Chinese Journal of Microsurgery 2021;44(2):232-234
In February, 2019, a patient with a defect of open dorsal cartilage and bone in the first metatarsal head, including the defects of soft tissue, tendon and joint capsule, was treated in our department. After multiple debridement, the vascularised medial femoral condyle osteochondral chimeric tissue flap was transferred to repair the composite tissue defect in the metatarsal head at the second stage. After 18 months of follow-up, the patient felt no pain in the foot and walking, and there was no sign of lameness and discomfort at donor sites. The postoperative functional recovery was satisfactory.
7.The clinical characteristics and perioperative management of complicated placenta increta
Liuying ZHONG ; Dunjin CHEN ; Chunhong SU ; Fang HE ; Lin YU ; Mei ZHONG
The Journal of Practical Medicine 2016;32(17):2837-2840
Objective To study the clinical characteristicsand perioperative managementof complicated placenta increta, effectively reduce the maternal adverse perinatal outcomes. Methods Retrospective analysis 25 cases of complicated placenta increta between January 2013 and December 2015 in the Third Affiliated Hospital Of Guangzhou Medical University. Grouped into preoperative line 9 cases of ureteral catheter group and without catheter group 16 cases; Conventional hysterectomy group of 17 cases and the posterior hysterectomy group of 8 cases , compare the operation time , postpartum hemorrhage , blood transfusion amount , bladder injury or ureteral injury rate , rate of transferred to the ICU and hospital stay. Results 76% appear repeatedly painless vaginal bleeding during pregnancy , 56% appear bleeding before delivery. Prenatal diagnosis of 17 cases (68%). The preoperative line cystoscopy + bilateral retrograde ureteral catheter or after the posterior hysterectomy , shorter operation time , less postpartum hemorrhage , reduce blood transfusion volume , no urinary tract injury rate, transferred to the ICU rate is low, the difference was statistically significant (P < 0.05). Conclusions We should attach importance to repeated painless vaginal bleeding , improve prenatal diagnostic rate of complicated placenta increta. The perioperative managementis more comprehensive , effective and standard participation , preoperative ureteral catheter and the posterior hysterectomy can effectively reduce the maternal adverse perinatal outcomes.
8.Clinical Study on CLIF-C OFs for Distinguishing Acute-on-chronic Liver Failure in Non-HBV-related Chronic Liver Disease with Acute Decompensation
Ru DING ; Bo ZENG ; Liuying CHEN ; Shuting LI ; Nannan ZHANG ; Hai LI
Chinese Journal of Gastroenterology 2015;(10):581-586
Background:A recent perspective European study has shown that Chronic Liver Failure-Consortium Organ Failure score(CLIF-C OFs)is an effective diagnostic criteria for acute-on-chronic liver failure(ACLF)in alcoholic or hepatitis C virus patients with acute decompensation(AD). Aims:To assess the efficacy of CLIF-C OFs for distinguishing ACLF in non-hepatitis B virus(HBV)-related chronic liver disease patients with AD. Methods:A total of 274 consecutive non-HBV-related chronic liver disease patients with AD from Jan. 2005 to Dec. 2010 at Shanghai Ren Ji Hospital were enrolled. Patients were divided into three groups:ACLF at admission,ACLF developed within 28-day and non-ACLF according to CLIF-C OFs criteria. Clinical and biochemistry characteristics,severity of the disease and 28-day and 90-day mortality data between ACLF and non-ACLF groups were analyzed. Results:Of the patients assessed,40 had ACLF at admission,27 had ACLF developed within 28-day,207 remained not having ACLF. Patients in ACLF group had higher TB,Cr,INR,ALT,AST,ALB,WBC,score of Child-Pugh,CTP,MELD,MELD-Na than non-ACLF patients(P <0. 05),and were younger in age(P < 0. 01). Incidences of hepatic,renal,cerebral,coagulation,circulation and lung failure,28-day mortality,90-day mortality were significantly higher in ACLF group than in non-ACLF patients( P <0. 01). However,no significant differences were seen in the characteristics mentioned above between ACLF at admission group and ACLF developed at 28-day group(P > 0. 05). TB level at admission and infection occurred within 28-day were the risk factors for developing ACLF(P < 0. 05). Conclusions:ACLF constitutes a more severe subgroup in non-HBV-related chronic liver disease patients with AD,and CLIF-C OFs could help to distinguish ACLF patients out from non-HBV-related chronic liver disease patients with AD.
9.Establishment of Model of Dynamic Change of Immune Status of ACLF Induced by ConA Repeated Administration in Mice
Nannan ZHANG ; Shuyin YANG ; Liuying CHEN ; Shan YIN ; Shijin WANG ; Sanhai LIU ; Beibei WANG ; Zheng WANG ; Hai LI
Chinese Journal of Gastroenterology 2016;21(6):326-330
Background:Acute-on-chronic liver failure( ACLF)is a commonly seen liver failure in China,and lacking an animal model that can effectively simulate the dynamic change of immune status of ACLF. Aims:To establish an animal model that can simulate dynamic change of immune status of ACLF by repeated administration of concanavalin A(ConA). Methods:Mice were randomly divided into normal control group and ConA repeated administration group. Mice in ConA repeated administration group were injected with ConA 15 mg/ kg through retrobulbar angular vein every 48 hours for 5 times,and mice in control group were injected with same volume of 0. 9% NaCl solution. Serum levels of IL-6,IL-10,IL- 12,TNF-α,IFN-γ,MCP-1 in peripheral blood were assessed by CBA assay,and the ratio of IL-10/ TNF-α was calculated. The expression of HLA-DR,number and proportion of CD4+ T cells and the expression of PD-1 of monocytes in peripheral blood were detected by flow cytometry. Results:Peripheral blood cytokines changed from predominated proinflammatory cytokines into predominated anti-inflammatory cytokines with the increasing in time of administration in ConA repeated administration group. Compared with control group,HLA-DR expression of monocytes in peripheral blood was significantly decreased(P <0. 05),number and proportion of CD4+ T cells were significantly decreased(P <0. 05), and PD-1 expression was significantly increased( P < 0. 05)in ConA repeated administration group. Conclusions:An animal model of ACLF immune status from systemic inflammatory response syndrome( SIRS) to compensatory antiinflammatory response syndrome(CARS)induced by repeated ConA stimulation is successfully established.
10.Three-dimensional finite element analysis of the effect of orbital implant lengths on stress distributions in peri-implant ;surfaces
Xing ZHANG ; Songling CHEN ; Yun ZHANG ; Liuying QI
West China Journal of Stomatology 2014;(5):484-487
Objective This study aims to observe the effect of orbital implant lengths on stress distribution in peri-implant surfaces. Methods The three-dimensional finite element analysis models of craniofacial and orbital implants with a diameter of 3.75 mm and lengths of 3, 4, 6, and 10 mm were established. A force of 20 N was applied to the models. The stress and displacement distribution under every condition were recorded and analyzed. Results The loading direction along the implant axis and the stress concentration on the implant root were observed. The loading direction was at a 45 degree angle relative to the implant axis, and the stress concentration was located at the implant neck and the first screw thread. The maximum stress of the 3 mm implant was significantly higher than that under the other two loading directions. The maximum displace-ment of the four lengths exhibited no significant change. Given the same implant length, stress, and displacement, the peak of the implant axial direction was lower than that of the 45 degree direction. The loading type was an important factor influencing the stress and displacement of peri-implant bones. Conclusion The implants of more than 4 mm length can be considered for clinical use. The implant of 3 mm length should be implanted in a region with thicker cortical bone.